Project Summary/Abstract Regular physical activity at moderate to vigorous levels is known to reduce risk for cancer. The majority of adults, however, do not obtain sufficient levels of physical activity to derive the health benefits. The low level of physical activity among young women is of particular concern. The proposed study uses existing secondary data collected in an NIH-funded randomized controlled aerobic exercise training intervention called Women In Steady Exercise Research (WISER), part of the University of Minnesota's Transdisciplinary Research on Energetics and Cancer (TREC) center (U54CA116849). The aim of this study is to explore how patterns of physical activity among young women may be changed by selected social contextual factors. Specific aims are: 1) to determine the modes, frequency and duration of physical activity that young, healthy, but inactive women engage in before and after a physical activity intervention, and the variations;2) to characterize young women's motivations for physical activity and to determine whether or not these motivations change following a physical activity intervention;3) to evaluate qualitative data collected from a subsample of 60 participants on socio-cultural norms on body image in young women's social networks, and implications for physical activity;4) to characterize how life circumstances, events and transitions affect women's physical activity;5) to evaluate data collected from a subsample of 60 participants on destinations, distances and modes of transport to then assess socio-environmental influences on their walking and bicycling. Data draws from enrolled WISER participants [N = 160 exercise intervention and 160 controls], who at baseline were ages 18-30 and inactive (reporting two or fewer times per week of exercise in prior six months), but otherwise healthy. During the study, women in the intervention group participated in aerobic exercise 5 times weekly for 30 minutes during 4 months at 65-85% of their age-predicted heart rate maximum. The primary analytic tool will be the generalized linear mixed model to allow subject- specific models with correlation of measures within woman over time. Results of the proposed research will allow us to gain a closer and more dynamic understanding of behavioral cancer risk factors, in particular how life conditions and contextual factors combine with socio-cultural factors to affect physical activity among young women. This research aims to inform future cancer prevention health promotion research and intervention efforts to improve energy balance through an integrative focus on how, where and why young women incorporate physical activity into their lives. PUBLIC HEALTH RELEVANCE: Project Narrative This study aims to examine how levels of and motivations for physical activity among 320 young women aged 18-30 years may be affected by these factors: a physical activity intervention, socio- cultural norms on body image;life transitions;and their modes of transport. Results of the proposed research will allow us to gain a closer and more dynamic understanding of lifestyle cancer risk factors. This research aims to inform future cancer prevention health promotion research and intervention efforts to improve energy balance through an integrative focus on how, where and why young women incorporate physical activity into their lives.